The present invention relates to a wing structure and method of assembling the wing structure, and more particularly to a wing structure in which the components can be slid into place without substantially employing any external fastening or clamping means.
Although many different types of wing constructions have been used in the building of model airplanes, these usually require clamping and/or gluing of individual components that are most commonly formed from balsa wood. This usually entailed gluing flat ribs to a central spar member and thereafter gluing leading edge and trailing edge members to the respective leading and trailing edges of the ribs. In addition to being tedious and time consuming, the glued wing structure of the prior art often resulted in a final wing assembly that was not accurate in accordance with the drawings and specifications supplied by the manufacture of the model airplane kit. The accuracy of wing construction in the assembly of model airplanes has become very important with the advent of model airplane designs, which now closely replicate the actual aircraft designs that the model has been derived from. The model airplane kits of today are usually produced from computer controlled laser cutting machines that produce accurate component parts that meet very exacting specifications. Accordingly, these new laser manufacturing techniques, together with the advent of sheathing the exterior with plastic type skin and providing modern solid state radio controls, has resulted in model airplanes that can reach speeds of over a hundred miles per hour with maneuverability that equals or even surpasses the actual aircraft from which the model airplane has been derived. Thus, the importance of accurate wing construction achieved by the present invention is greatly magnified when operating model airplanes at high speeds with greater maneuverability, and even small changes from the specifications in the assembled model wing could result in very poor flight performance of the respective model airplane. The present invention provides for ease of assembly of model wings that are very accurate with respect to the specifications and drawings, whereby an aerodynamic self-aligning wing structure can be readily achieved.
The unique main spar design of the present invention affords several additional advantages, one of which is the ability to use it with conventional prior art structural members, such as leading edge and trailing edge strips which are glued to the respective leading rib edges and trailing rib edges in the usual manner. The other advantage achieved through the main spar of the present invention, is the amelioration or even complete elimination of what is commonly known in the art as "wing tip stall" which as used herein means preventing stalling in the wing tip location prior to the rest of the wing structure, which increases as the angle of attack of the wing increases. By varying the angle of the slots in the ribs at the wing tip location, it is possible to rotate the wing tip in a downward direction and provide a uniformly tilted wing tip. Thus, the wing tip will have greater lift than the remainder of the wing, whereby the entire wing will have a more uniform stall characteristic. This is commonly known in the art as "wing tip washout" wherein the wing tip does not prematurely stall. Also, the uniformly tilted wing tip of the present invention, eliminates the need for the use of the prior art use of jigs and/or sheathing commonly used to twist the wing tip downwardly, which often resulted in creating unwanted non-uniformity and constraining forces on the wing structure.
By providing a design and method in accordance with the present self-aligning wing construction, it is possible to slide all of the major wing components into place, such that an aerodynamic wing structure has been achieved prior to gluing of the component parts from which the wing is comprised. In this manner, the wing structure, which has been slid together, can be glued along the abutting edges of the component parts without disturbing their location and causing misalignment. Thus, the gluing is not relied upon for positioning the wing components of the present invention but only to hold them together, wherein the glue merely strengthens the self aligning wing structure without changing the aerodynamic shape of the wing.